Added cURL section

Author: spelluru

articles/event-grid/mqtt-how-to-http-publish.md

@@ -16,7 +16,7 @@ ms.custom:
 ---
 
 # How to Publish MQTT Messages via HTTP with Azure Event Grid
-Azure Event Grid now supports publishing MQTT messages via HTTP, enabling backend systems to send messages to devices without maintaining persistent MQTT connections. This approach simplifies integration for applications that prefer stateless communication, leverages secure authentication with Entra ID, and provides scalable, reliable delivery to MQTT clients. In this article, you'll learn how to use the HTTP Publish API, obtain the necessary credentials, and verify message delivery using popular tools like Postman, Bruno, and MQTTX.
+Azure Event Grid now supports publishing MQTT messages via HTTP, enabling backend systems to send messages to devices without maintaining persistent MQTT connections. This approach simplifies integration for applications that prefer stateless communication, uses secure authentication with Entra ID, and provides scalable, reliable delivery to MQTT clients. In this article, you learn how to use the HTTP Publish API, obtain the necessary credentials, and verify message delivery using popular tools like Bruno, and MQTTX.
 
 This article explains how to publish MQTT messages via HTTP with Azure Event Grid. 
 
@@ -30,114 +30,67 @@ This article explains how to publish MQTT messages via HTTP with Azure Event Gri
 Run the following Azure CLI command to get a bearer token. 
 
 ```bash
-az account get-access-token --resource=https://<namespace> --query accessToken -o tsv
+az account get-access-token --resource=https://<namespaceFQDN> --query accessToken -o tsv
 ```
 
-## Import to Bruno
-Use a tool such as Bruno to 
+Save this token to use in the `Authorization: Bearer <TOKEN>` header. 
 
-1. Open Bruno.
-1. Select **Import Collection**, and then select `EventGrid_HTTP_Publish_Postman_Collection.json`.
-1. Go to **Variables** tab:
-   - Replace `{{namespace}}` with your namespace FQDN.
-   - Replace `{{topic}}` with your MQTT topic.
-   - Replace `{{entra_token}}` with your token from Step 2.
-1. Select **Send** — you should get 202 or 204.
-
-## Step 4: Verify in MQTTX
+# [cURL](#tab/curl)
 
-- Open MQTTX and connect using your broker’s endpoint, TLS, and your normal MQTT auth.
-- Subscribe to the topic you used in the HTTP POST.
-- You should see your payload appear.
-
-## Troubleshoot
+Here’s an example cURL command to simulate the HTTP Publish. 
 
-- **401 Unauthorized?** — Refresh your token.
-- **403 Forbidden?** — Check your topic or permissions.
-- **Message doesn’t appear?** — Ensure topic is percent-encoded in the URL, check broker routing config, and verify you’re using the same namespace.
-
-
-# Tutorials:
-
-## Option 1: Using cURL Command
-
-### Step 1: Get Your Connection Details
-
-- **Event Grid Namespace**: e.g., contoso.westus3-1.ts.eventgrid.azure.net
-- **Topic**: e.g., devices/CXa-23112/prompt
-- **Entra Client ID** and Tenant: for getting your bearer token.
-- **Audience (Resource)**: your Event Grid Namespace URL.
-
-### Step 2: Get an Entra ID Token
-
-Use **Azure CLI** or your preferred flow to get a token:
-
-```bash
-az account get-access-token \
-  --resource=https://contoso.westus3-1.ts.eventgrid.azure.net \
-  --query accessToken \
-  -o tsv
+```http
+curl -X POST "https://contoso.westus3-1.ts.eventgrid.azure.net/mqtt/messages?topic=devices%2XXXX-0000%2Fprompt&api-version=2025-02-15-preview" \ 
+  -H "Authorization: Bearer <ENTRA_TOKEN_HERE>" \ 
+  -H "mqtt-qos: 1" \ 
+  -H "mqtt-retain: 0" \ 
+  -H "mqtt-response-topic: devices%2XXXX-00000%2Freply" \ 
+  -H "mqtt-correlation-data: XXXXXXX" \ 
+  -H "mqtt-user-properties: XXXXXXXXXXXX" \ 
+  -H "Content-Type: text/plain;charset=UTF-8" \ 
+  --data-raw "Please accept terms of licensing and agreement" 
 ```
 
-Save this token to use in the Authorization: Bearer `<TOKEN>` header.
+In this sample command:
 
-### Step 3: Prepare Your HTTP POST Request
+- Topic is percent-encoded. 
+- Add optional headers for QoS, retain flag, response topic, user properties. 
+- Payload goes in the request body. 
 
-Here’s an example using curl to simulate the HTTP Publish.
+# [Bruno](#tab/brno)
 
-```bash
-curl -X POST "https://contoso.westus3-1.ts.eventgrid.azure.net/mqtt/messages?topic=devices%2FCXa-23112%2Fprompt&api-version=2025-02-15-preview" \
-  -H "Authorization: Bearer <ENTRA_TOKEN_HERE>" \
-  -H "mqtt-qos: 1" \
-  -H "mqtt-retain: 0" \
-  -H "mqtt-response-topic: devices%2FCXa-23112%2Freply" \
-  -H "mqtt-correlation-data: PlXCscK2wrbCuy8=" \
-  -H "mqtt-user-properties: W3siVXJnZW5jeSI6ImFsZXJ0In0seyJSZXF1ZXN0SWQiOiI1NWY0YTdlZS1iMGI0LTRkN2YtOGViNS0yZWRiYTJjZWQ1ZDcifV0=" \
-  -H "Content-Type: text/plain;charset=UTF-8" \
-  --data-raw "Please accept terms of licensing and agreement"
-```
-
-### Step 4: Verify Publish with MQTT Client
+## Import to Bruno
+1. Open Bruno.
+1. Select **Import Collection**, and then select `EventGrid_HTTP_Publish_Postman_Collection.json`.
+1. Go to **Variables** tab:
+   - Replace `{{namespace}}` with your namespace FQDN.
+   - Replace `{{topic}}` with your MQTT topic.
+   - Replace `{{entra_token}}` with your token from Step 2.
+1. Select **Send**. You should get 202 or 204.
 
-Use **MQTTX** or any MQTT library (like paho-mqtt Python) to subscribe to the same topic to confirm delivery.
+---
 
-#### Example MQTTX Steps
+## Step 4: Verify in MQTTX
+Use MQTTX or any MQTT library (like paho-mqtt Python) to subscribe to the same topic to confirm delivery. 
 
 1. Create a new connection in MQTTX:
-   - Host: contoso.westus3-1.ts.eventgrid.azure.net
-   - Port: 8883 (TLS)
-   - Client ID: same as your Entra Object ID.
-   - Username/Password: N/A — use certificate or token auth if configured.
-2. Subscribe to devices/CXa-23112/prompt.
-3. Run the HTTP Publish and watch for the message in MQTTX.
-
-### Step 5: Validate Success
-
-- If the publish succeeds, you’ll see:
-  - **HTTP Response**: 204 No Content or 202 Accepted (depending on routing rules).
-  - MQTT client sees the message instantly.
-
-#### Expected log in your MQTT client
+    1. `Host: contoso.westus3-1.ts.eventgrid.azure.net`
+    1. `Port: 8883 (TLS)`
+    1. `Client ID: same as your Entra Object ID` 
+    1. `Username/Password: N/A — use certificate or token auth if configured`   
+- Subscribe to the topic you used in the HTTP POST command.
+- Run the **HTTP Publish** and watch for the message in MQTTX. You should see your payload appear.
 
-```text
-Topic: devices/CXa-23112/prompt
-Payload: Please accept terms of licensing and agreement
-QoS: 1
-```
-
-### Step 6: Handle Failures
-
-- If the token is missing or expired: You’ll get 401 Unauthorized.
-- If the topic is invalid or you don’t have rights: 403 Forbidden.
-- If routing fails internally: 500 Internal Server Error with diagnostic info.
+If the publish **succeeds**, you see: 
 
-💡 Check logs in Event Grid Metrics and Diagnostic Logs for delivery status.
+- **HTTP Response**: 204 No Content or 202 Accepted (depending on routing rules). 
+- MQTT client sees the message instantly. 
 
-## Option 2: Using Postman or Bruno
+## Troubleshoot
 
-This helps you test the HTTP Publish feature using:
+- **401 Unauthorized?** — If the token is missing or expired: You get 401 Unauthorized. Refresh your token.
+- **403 Forbidden?** — If the topic is invalid or you don’t have rights: 403 Forbidden. Check your topic or permissions.
+- **500 Internal Server Error** - If routing fails internally, check metrics and diagnostic Logs for your Event Grid namespace. 
+- **Message doesn’t appear?** — Ensure topic is percent-encoded in the URL, check broker routing config, and verify you’re using the same namespace.
 
-- Postman or Bruno collection (provided).
-- MQTTX or your MQTT client to verify delivery.
-- Entra ID for secure auth.